Presentation 1: Emeline Georges (Haulogy)

Title: Interactions between TSOs and DSOs: a practical case study from Wallonia for congestion management

Abstract: With the energy transition, electricity networks are increasingly being operated close to their limits. The risks of congestion and voltage problems in transmission networks are increasing significantly, and effective interaction between TSOs and DSOs is essential to ensure network security. With this in mind, Haulogy has developed a software solution that retrieves, in real time, the power limits sent by the TSO to the substations at the interface between the transmission network and the distribution network. It optimizes the commands to be sent to flexible users of the medium-voltage network, such as decentralized generation, in order to comply with the TSO’s limits and thus reduce congestion in the transmission network. During this presentation, we will present the tool developed by Haulogy and give a demonstration in the Walloon context. We will also discuss the options being considered for managing voltage problems.

Presentation 2: Olivier Bronckart (Elia)

Title: Evolution of voltage and MVAr management in the Belgian transmission power system

Abstract: Power systems are facing major changes, including the development of renewable energy leading to increasing decentralization of production; environmental constraints leading to cables replacing overhead lines from distribution up to EHV systems; and technological evolution, with power electronics resulting in less inductive load behavior. As a consequence, the MVAr behavior of the power system is shifting significantly from inductive to increasingly capacitive, resulting in higher and higher voltages. This presentation will illustrate how Elia, as the transmission system operator, needs to adapt its investments, the technical requirements for new or modernized loads and generation, the conditions for MVAr ancillary services, and its operational processes in order to ensure sufficient resources and optimize their use for secure operation of the transmission system.

Date & Time: Monday March 03, 2026 - 9:30 AM to 11:45 AM

Location: R7, Building B28, Montefiore Institute